The major objectives of this project are to study immunological mechanisms of host defense against acute, persistent, and latent viral infections. These studies are focused on in vitro assays for determining the effects of immunologically induced mediators, humoral immunity and cell-mediated immunity on herpes simplex virus and vaccinia virus infected cells. In addition, in vivo models are being used to study whether the results obtained with the in vitro models could be applicable to localized vaccinia virus infections in rabbit skin and systemic virus infections of mice.